Facing Japanese giants Gamba Osaka in their first group game, United were handed a convincing 3-0 defeat at Hindmarsh Stadium.

Coming into the clash with some confidence after a much needed 1-0 win over Newcastle Jets in the A-League, Adelaide never really looked like causing an upset as their first group game ended in defeat.

United now face Melbourne Victory in the A-league on Saturday before facing an away game against Jiangsu Suning FC in their second group game of the ACL.